Coachman 12V RV Wiring Route

Chazzer

Chazzer

Member
Sep 11, 2012
83
6
8
Southern Ontario
Howdy Folks,

Does anyone have knowledge on the routing of the 12V RV wiring for a 1978 Coachman Center Kitchen? I have developed a ground fault issue with the 12V
house lighting on the right side. When I go back to the fuse panel at the back it would appear the wiring exits the fuse panel and goes down towards
the left side. I have a few things in the way of seeing where the wiring heads after it goes left. Somewhere the wiring must make it's way up and over
to the right but where?

Any help on that issue as well as any pointers on trying to locate the ground fault would be greatly appreciated. The fuse blow instantly.

Thanks, Jim
--
Jim Owens,

78 Royale,

Out skirts of Kitchener, Ontario
 
Have you tried disconnecting it at the first fixture in the chain on that side. If fuse does not blow the problem is after or at that first fixture.
Then you can search in the correct zip code. Coachmen were not as “by the book” aa GM upfits is what I hear, so schematics may be close but
not.exact as to wire colors etc.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
I disconnected the rear lamp as I assumed it would be the first in line. Noticed the wires going to the lamp were coming from the front of the
cabinet. So I then disconnected the light in the center of the coach in the kitchen area as perhaps this may be the first in the series depending on
where the wires come from. Fuse still blows with both fixtures out of the loop. I have a wire grounding out to the body somewhere...fun and games....
--
Jim Owens,

78 Royale,

Out skirts of Kitchener, Ontario
 
Do you still have the original glass fuse house panel? If so I would remove
it from its mounts and start there. Maybe the wire has heated up and shed
insulation.

Have you done ANY work on the interior between when the lights worked
correctly and now? I once had a short to ground caused by nicking a wire
with an interior trim screw.

Sully
Bellevue wa

> I disconnected the rear lamp as I assumed it would be the first in line.
> Noticed the wires going to the lamp were coming from the front of the
> cabinet. So I then disconnected the light in the center of the coach in
> the kitchen area as perhaps this may be the first in the series depending on
> where the wires come from. Fuse still blows with both fixtures out of the
> loop. I have a wire grounding out to the body somewhere...fun and games....
> --
> Jim Owens,
>
> 78 Royale,
>
> Out skirts of Kitchener, Ontario
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
 
It does have the original glass fuses in the back.

I have not done any interior work, I have been working on the body though and I relocated the right rear outside clearance light to accommodate the
new awning I have on order. I had to tug on the wires a bit and if the Coachman wiring was routed up by the OE GM wiring than I guess it's possible I
pulled something loose from the Coachman wiring. It definitely is a big mystery why all of a sudden I have the issue.

--
Jim Owens,

78 Royale,

Out skirts of Kitchener, Ontario
 
Take the screws back out that you added and try the fuse again.

Sully
Bellevue wa

> It does have the original glass fuses in the back.
>
> I have not done any interior work, I have been working on the body though
> and I relocated the right rear outside clearance light to accommodate the
> new awning I have on order. I had to tug on the wires a bit and if the
> Coachman wiring was routed up by the OE GM wiring than I guess it's
> possible I
> pulled something loose from the Coachman wiring. It definitely is a big
> mystery why all of a sudden I have the issue.
>
>
> --
> Jim Owens,
>
> 78 Royale,
>
> Out skirts of Kitchener, Ontario
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
>
 
Well, I've figured out the problem. The hot wire from the center aisle kitchen light is grounding out somewhere between the center fixture and it's
next stop at the entrance way light switch. I'm wondering if the storage pod has something to do with it. I had removed the pod to refinish the roof.
I reinstalled it using the exact same holes with the exact same hardware. I may try and pull out some of the pod fasteners and see what happens.


--
Jim Owens,

78 Royale,

Out skirts of Kitchener, Ontario
 
Jim,
What are the chances of pulling a new wire from the center kitchen light over to the entrance way light switch? If that is possible, then you could
cut off the existing shorted wire and label it "shorted" if it won't come out.

If that is not possible, then back off the pod screws on the right side of the coach near the center kitchen light area. If that fixes the short, see
if you can move the wire a bit to get it away from the screw. You could then add a couple of washers under the screws you loosened. Then I would add
a fuse in the line over to the switch and put the smallest amp fuse that would operate the entrance way light. That way if the short happens again,
minimum short circuit current will blow that fuse.

--
Bruce Hislop
ON Canada
77PB, 455 Dick P. rebuilt, DynamicEFI EBL EFI & ESC.1 ton front end
http://www.gmcmhphotos.com/photos/showphoto.php?photo=29001
My Staff says I never listen to them, or something like that
 
Bruce,

Thanks for the great suggestions. Chances are I will not be able to run a new wire with out ripping half the motorhome apart. I will look into the
other suggested options at this time. The headliner does need to be addressed but that's a project for another winter. So may even have a temporary
solution in place till then.

I will be calling on you at some point to discuss the best way to isolate my two Coachmen batteries(generator and house) again soon, I know you gave
me some input before but apparently I've forgotten!
--
Jim Owens,

78 Royale,

Out skirts of Kitchener, Ontario
 
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